Antennas are commonly employed in devices such as radio frequency identification (RFID) tags and mobile telephones that are deployed in a range of environments. Antennas generally exhibit different characteristics in free space than when in proximity to a conductive ground plane (e.g., a metal surface). For instance, the power delivered to a conventional antenna given constant power available at a feed of the antenna may be significantly less when the antenna is in proximity to a ground plane as compared to when the antenna is in free space, or vice versa. Conventionally, antennas have been constructed so as to be tuned to function either in free-space environments or environments in proximity to ground planes, not both. While a conventional antenna can be operated both in free space and near ground planes, generally such an antenna will exhibit significant loss in one environment or the other, potentially rendering the conventional antenna unusable for its intended purpose in one environment or the other.